//=============================================================================
//! Samll Real Double-precision Symmetric Matrix Class
template<CPPL_INT n> class dsymatrix_small
{
public:
///////////////////////////////////////////////
/////////////////// objects ///////////////////
///////////////////////////////////////////////
double array[(n*(n+1))/2]; //!< 1D array to store vector data
///////////////////////////////////////////////
///////////////// constructors ////////////////
///////////////////////////////////////////////
inline dsymatrix_small();
inline explicit dsymatrix_small(const dsymatrix&);
inline ~dsymatrix_small();
///////////////////////////////////////////////
////////////////// functions //////////////////
///////////////////////////////////////////////
//////// cast ////////
inline dgematrix_small<n,n> to_dgematrix_small() const;
inline dsymatrix to_dsymatrix() const;
//////// io ////////
inline double& operator()(const CPPL_INT& i, const CPPL_INT& j);
inline double operator()(const CPPL_INT& i, const CPPL_INT& j) const;
inline dsymatrix_small<n>& set(const CPPL_INT&, const CPPL_INT&, const double&);
template<CPPL_INT _n> inline friend std::ostream& operator<<(std::ostream&, const dsymatrix_small<_n>&);
inline void read(const char* filename);
inline void write(const char* filename) const;
//////// misc ////////
inline dsymatrix_small<n>& zero();
inline dsymatrix_small<n>& identity();
///////////////////////////////////////////////
///////////// numerical operators /////////////
///////////////////////////////////////////////
#ifndef _MSC_VER
//////// = ////////
template<CPPL_INT N> inline dsymatrix_small<N>& operator= (const dsymatrix_small<N>&);
//////// += ////////
template<CPPL_INT N> inline friend dsymatrix_small<N>& operator+=(dsymatrix_small<N>&, const dsymatrix_small<N>&);
//////// -= ////////
template<CPPL_INT N> inline friend dsymatrix_small<N>& operator-=(dsymatrix_small<N>&, const dsymatrix_small<N>&);
//////// *= ////////
template<CPPL_INT N> inline friend dsymatrix_small<N>& operator*=(dsymatrix_small<N>&, const double&);
//////// /= ////////
template<CPPL_INT N> inline friend dsymatrix_small<N>& operator/=(dsymatrix_small<N>&, const double&);
//////// unary ////////
template<CPPL_INT N> inline friend const dsymatrix_small<N>& operator+(const dsymatrix_small<N>&);
template<CPPL_INT N> inline friend dsymatrix_small< N > operator-(const dsymatrix_small<N>&);
//////// + ////////
template<CPPL_INT N> inline friend dgematrix_small<N,N> operator+(const dsymatrix_small<N>&, const dgematrix_small<N,N>&);
template<CPPL_INT N> inline friend dsymatrix_small< N > operator+(const dsymatrix_small<N>&, const dsymatrix_small< N >&);
//////// - ////////
template<CPPL_INT N> inline friend dgematrix_small<N,N> operator-(const dsymatrix_small<N>&, const dgematrix_small<N,N>&);
template<CPPL_INT N> inline friend dsymatrix_small< N > operator-(const dsymatrix_small<N>&, const dsymatrix_small< N >&);
//////// * ////////
template<CPPL_INT N> inline friend dcovector_small< N > operator*(const dsymatrix_small<N>&, const dcovector_small< N >&);
template<CPPL_INT M, CPPL_INT N> inline friend dgematrix_small<M,N> operator*(const dsymatrix_small<M>&, const dgematrix_small<M,N>&);
template<CPPL_INT N> inline friend dgematrix_small<N,N> operator*(const dsymatrix_small<N>&, const dsymatrix_small< N >&);
template<CPPL_INT N> inline friend dsymatrix_small< N > operator*(const dsymatrix_small<N>&, const double&);
//////// / ////////
template<CPPL_INT N> inline friend dsymatrix_small< N > operator/(const dsymatrix_small<N>&, const double&);
//////// double ////////
template<CPPL_INT N> inline friend dsymatrix_small< N > operator*(const double&, const dsymatrix_small< N >&);
//////// hadamerd ////////
template<CPPL_INT N> inline friend dsymatrix_small< N > hadamerd(const dsymatrix_small<N>&, const dgematrix_small<N,N>&);
template<CPPL_INT N> inline friend dsymatrix_small< N > hadamerd(const dsymatrix_small<N>&, const dsymatrix_small< N >&);
#endif//_MSC_VER
};
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
inline double det(const dsymat2&);
inline dsymat2 inv(const dsymat2&);
inline dsymat2 rotate(const dsymat2&, const double&);
inline double det(const dsymat3&);
inline dsymat3 inv(const dsymat3&);
inline dsymat3 rotate(const dsymat3&, const dquater&);